Add godoc documentation to exported types and methods

Add proper godoc comments to exported items in:
- internal/globals: Appname, Version, Commit variables; Globals type; New function
- internal/log: LogLevel type; level constants; Config type; Initialize, Fatal,
  Error, Warn, Notice, Info, Debug functions and variants; TTYHandler type and
  methods; Module variable; LogOptions type

internal/log/module.go

@@ -4,19 +4,19 @@ import (
 	"go.uber.org/fx"
 )
 
-// Module exports logging functionality
+// Module exports logging functionality for dependency injection.
 var Module = fx.Module("log",
 	fx.Invoke(func(cfg Config) {
 		Initialize(cfg)
 	}),
 )
 
-// New creates a new logger configuration from provided options
+// New creates a new logger configuration from provided options.
 func New(opts LogOptions) Config {
 	return Config(opts)
 }
 
-// LogOptions are provided by the CLI
+// LogOptions are provided by the CLI.
 type LogOptions struct {
 	Verbose bool
 	Debug   bool